Quick Answer. A low hemoglobin count, also known as anemia, is caused by pregnancy, a menstrual period, a diet low in iron, blood loss, or a disease that causes the body to produce fewer red blood cells or to destroy red blood cells. According to the Mayo Clinic, medications also sometimes cause anemia.
A cytotoxic T cell (also known as TC, cytotoxic T lymphocyte, CTL, T-killer cell, cytolytic T cell, CD8+ T-cell or killer T cell) is a T lymphocyte (a type of white blood cell) that kills cancer cells, cells that are infected (particularly with viruses), or cells that are damaged in other ways.
Cytotoxic T cells. Cytotoxic T cells (TC cells, or CTLs) destroy virally infected cells and tumor cells, and are also cause much of the damage in in transplant rejection and autoimmune diseases. These cells are also known as CD8+ T cells since they express the CD8 glycoprotein at their surface.